title: Kainic acid, tetrodotoxin and light modulate expression of brain-derived neurotrophic factor in developing avian retinal ganglion cells and their tectal target.
abstract: Increasing evidence underlies the importance of neurotrophins as neuron-derived trophic signals in the developing visual system, although their precise roles are still undefined. Here we show that brain-derived neurotrophic factor messenger RNA is simultaneously expressed in a subpopulation of retinal ganglion cells and in their target during late embryogenesis. Moreover, light as well as the excitotoxin; kainic acid, induced an increase of the brain-derived neurotrophic factor messenger RNA, which could be blocked by the sodium-channel blocker; tetrodotoxin. Messenger RNA for trkB, a receptor for brain-derived neurotrophic factor, was found in the retinal ganglion cells expressing brain-derived neurotrophic factor showing that certain retinal ganglion cells express messenger RNA both for brain-derived neurotrophic factor and trkB. Furthermore, trkB messenger RNA was found in tectum, in the same layers as the brain-derived neurotrophic factor messenger RNA. These findings suggest that brain-derived neurotrophic factor expression is regulated in an activity-dependent manner during the phase of development when neuronal activity plays an important role.
authors.affiliation: Department of Developmental Neuroscience, BMC, Uppsala University, Sweden.
authors.forename: M
authors.initials: M
authors.lastname: Karlsson
authors.forename: F
authors.initials: F
authors.lastname: Hallböök
mesh_terms: D000818:Animals; D019208:Brain-Derived Neurotrophic Factor / Q000096:biosynthesis*; D002642:Chick Embryo; D018690:Excitatory Amino Acid Agonists / Q000494:pharmacology*; D005456:Fluorescent Dyes; D005786:Gene Expression Regulation / Q000502:physiology; D017403:In Situ Hybridization; D007608:Kainic Acid / Q000494:pharmacology*; D008027:Light; D012333:RNA, Messenger / Q000096:biosynthesis; D020794:Receptor Protein-Tyrosine Kinases / Q000096:biosynthesis; D020801:Receptor, Ciliary Neurotrophic Factor; D017475:Receptors, Nerve Growth Factor / Q000096:biosynthesis; D012165:Retinal Ganglion Cells / Q000187:drug effects / Q000378:metabolism* / Q000528:radiation effects; D013266:Stilbamidines; D013477:Superior Colliculi / Q000187:drug effects / Q000378:metabolism* / Q000528:radiation effects; D013779:Tetrodotoxin / Q000494:pharmacology*
chemical_list: C049774:2-hydroxy-4,4'-diamidinostilbene, methanesulfonate salt; D019208:Brain-Derived Neurotrophic Factor; D018690:Excitatory Amino Acid Agonists; D005456:Fluorescent Dyes; D012333:RNA, Messenger; D020801:Receptor, Ciliary Neurotrophic Factor; D017475:Receptors, Nerve Growth Factor; D013266:Stilbamidines; D013779:Tetrodotoxin; D020794:Receptor Protein-Tyrosine Kinases; D007608:Kainic Acid